Table 1.

Risk of bias.

+Low risk of bias - High risk of bias ? Unclear risk of bias X Not applicable	Apard (2010)	Donegan (2011)	El Afly (2015)	Gupta (2016)	Olesen (2015)	Stafford (2010)	Giannoudis (2016)	Zoller (2017)	Ma (2017)	Cho (2017)	Sasaki (2018)
Were there clear inclusion criteria for the case series?	+	+	+	+	+	+	+	+	+	+	+
Was the condition measured in a standard, reliable way for all participants included in the case series?	+	+	+	+	+	+	+	+	+	+	+
Were valid methods used to identify the condition for all participants included in the case series?	+	+	+	+	+	+	+	+	+	+	+
Did the case series include participants consecutively?	-	+	+	+	+	+	+	+	+	+	-
Did the case series involve complete inclusion of participants?	-	+	+	+	+	+	+	+	+	+	-
Was the reporting of the demographics of the participants in the study clear?	+	+	+	+	+	+	+	+	+	+	+
Was the reporting of the clinical information of the participants clear?	+	+	+	+	+	+	+	+	+	+	+
Were the outcomes or follow-up results of cases clearly reported?	+	+	+	+	+	+	+	+	+	+	+
Was the reporting of demographic information of the presenting site(s)/clinic(s) clear?	-	-	-	-	-	-	-	-	-	-	-
Was the statistical analysis appropriate?	X	X	X	X	X	X	X	X	X	X	X